> Please explain, for those of us not yet involved in Linux, why > it's not cost effective. For example, if we already have z/VM running, > there is no additional cost involved.
If you already pay for VM on your standard engines, the issue is less serious. But: 1) Standard engines are 4x (or more) the cost of an IFL for equivalent horsepower. 2) Standard engines increase the computed size of the box for software licensing purposes. This can be a killer for software in other LPARs, particularly z/OS-based products. 3) Standard engines can be crippled; IFLs always run at full speed. Price per MIP is much better on IFL, especially when you can get 4x horsepower for the same spend as 1 standard CPU. 4) If you license VM on standard engines, you have to license it for all the standard engines on the entire box, not just the IFLs in the LPAR in question. 5) Use of Linux on IFLs often reduces the need for other specialty engines that are useless to general-purpose workload (eg, ZIIP, ZAAP, etc which are useless to anything but z/OS). Better yield for same spend, and the IFLs benefit ALL Linux workload, not just one z/OS instance. It'll technically work fine; it just tends to not work out from the software licensing and pricing perspective.
